Field
The present disclosure relates to integrated and micro-fabricated magnetic circuits and methods of manufacturing thereof.
Description of the Related Art
Electromagnetic devices, such as inductors, transformers, and various other electromagnetic devices, utilize coils that pass through a cavity of a magnetic core. Conventional fabrication processes of such electromagnetic elements have been limiting in terms of size and density. Because cores known in the art have been commonly manufactured with multiple low-frequency magnetic components, power loss and parasitics are significant. Furthermore, micro-scale cores known in the art that provide closed magnetic flux path have structural discontinuities that impact flux loss. The micro-scale cores known in the art are also susceptible to flux bunching and spreading.
Micro-scale magnetic elements known in the art do not perform optimally under high frequencies and are therefore unsuitable for integration in power converter circuits (e.g., DC-DC converters). Furthermore, micro-scale magnetic elements have poor transient responses. The poor transient response is unsuitable for integration in power amplifiers of envelope tracking circuitry in which bias voltage is dynamically adjusted at a high frequency.
Therefore, there is a need in the art for micro-scale electromagnetic elements to provide a closed loop magnetic flux and significantly suppress or eliminate power loss. Furthermore, there is a need for a low-cost method of manufacturing and on-chip integration of micro-scale electromagnetic elements. In addition, there is a need in the art for micro-fabricated electromagnetic elements that perform optimally at high frequencies with a favorable transient response.